This invention relates to a memory card such as an IC card for use in a game machine and, more particularly, to a shutter for covering electrode terminals of the card.
The type of memory card that is used as an IC card which contains TV game software or as a desk card for use in a microcomputer system has a structure such as that shown in FIG. 1. A memory card 1 (hereinafter simply referred to as "card") has a multiplicity of electrode terminals 3 (refer to FIG. 2) disposed on the obverse surface of a package 2 at one end thereof. The package 2 accommodates a semiconductor module 2b in which thin semiconductor modules, electronic parts, a thin cell battery such as a mercury cell, and so forth are incorporated. A shutter 4 is formed from a thin metallic plate and adapted to cover the electrode terminals 3. The shutter 4 is supported in such a manner that it can open or close by sliding in the longitudinal direction of the card as indicated by the arrow A. The shutter 4 has a pair of downwardly bent projections 4a formed at its extreme ends. FIG. 3 shows the reverse side of the shutter 4. In order to reduce the thickness of the card 1 as much as possible, the shutter 4 is formed from a thin plate made of a metallic material such as stainless steel and is thereby improved in mechanical strength.
A return spring (not shown) is stretched between the shutter 4 and the package 2, and functions to close the shutter in a normal state.
To use the thus constructed card 1, the card is inserted into a connector disposed on the side of a card reader (both not shown), the projections 4a of the shutter 4 abut against the receiving pins disposed on the side of the connector, and the shutter 4 is thereby opened, as shown in FIG. 2. This exposes the electrode terminals 3 of the card 1 and bring them into contact with electrode-contacting pieces (not shown) of the connector, thereby electrically connecting the card to the card reader.
In this type of conventional memory card, a gap which is formed between the metal shutter 4 and the electrode terminals 3 is small, and there is a possibility of static electrical charge on the shutter being discharged to the electrode terminals 3 or a possibility of the shutter contacting the electrode terminals 3 and causing a short-circuit therebetween.